Semiconductor wafer defect detection using digital holography
Semiconductor wafer defect detection using digital holography
复制标题
使用数字全息技术检测半导体晶圆缺陷
DOI：
--
复制
发表时间：
2003
期刊：
影响因子：
--
通讯作者：
C. E. Thomas
中科院分区：
文献类型：
--
作者：
M. Schulze;M. Hunt;E. Voelkl;J. Hickson;W. Usry;Randall G. Smith;R. Bryant;C. E. Thomas
缺陷检测计量是半导体制造的良率斜坡和过程监控阶段的一个组成部分。在ITRS中，高纵横比结构已被确定为关键结构，其中不存在已知的用于缺陷检测的可制造解决方案。我们目前的数字全息的基础上，解决这一需求的新的检测技术的案例研究。数字全息术将来自目标物体的波前的振幅和相位直接记录到由CCD相机获取的单个图像中。使用深紫外激光照明，数字全息术能够分辨与小至几纳米的高度差相对应的相位差。因此，该技术非常适合于发现半导体晶片上的缺陷的任务。我们提出了几个缺陷检测基准晶片的研究，并比较数字全息检测的结果与其他晶圆检测技术。具体地，数字全息术允许对高纵横比特征（诸如不适当蚀刻的接触）的改进的缺陷检测。此外，数字全息术提供的相位信息使我们能够可视化缺陷的拓扑结构，甚至可以生成与扫描电子显微镜（SEM）图像相当的晶片表面的三维图像。这些结果证明了数字全息术独特的缺陷检测能力。
Defect inspection metrology is an integral part of the yield ramp and process monitoring phases of semiconductor manufacturing. High aspect ratio structures have been identified in the ITRS as critical structures where there are no known manufacturable solutions for defect detection. We present case studies of a new inspection technology based on digital holography that addresses this need. Digital holography records the amplitude and phase of the wavefront from the target object directly to a single image acquired by a CCD camera. Using deep ultraviolet laser illumination, digital holography is capable of resolving phase differences corresponding to height differences as small as several nanometers. Thus, the technology is well suited to the task of finding defects on semiconductor wafers. We present a study of several defect detection benchmark wafers, and compare the results of digital holographic inspection to other wafer inspection technologies. Specifically, digital holography allows improved defect detection on high aspect ratio features, such as improperly etched contacts. In addition, the phase information provided by digital holography allows us to visualize the topology of defects, and even generate three-dimensional images of the wafer surface comparable to scanning electron microscope (SEM) images. These results demonstrate the unique defect detection capabilities of digital holography.